Openable fin arrangement



July 23, 1963 J. R. JASSE 3,098,446

OPENABLE FIN ARRANGEMENT Filed July l0, 1961 5 Sheets-Sheet 1 om mm N m m SH Q July 23, 1963 J. R. JAssE 3,098,446

OPENABLE FIN ARRANGEMENT Filed July l0, 1961 5 Sheets-Sheet 2 July 23, 1963 J. R. JAssE OPENABLE FIN ARRANGEMENT 5 Sheets-Sheet 3 Filed July 10, 1961 July 23, 1963 J. R. JAssE OPENABLE FIN ARRANGEMENT 5 Sheets-Sheet 4 Filed July 10, 1961 July 23, 1963 J. R. JAssE OPENABLE FIN ARRANGEMENT 5 Sheets-Sheet 5 Filed July 10, 1961 United States Patent O 3,098,446 GPIENABLE EN ARRANGEMENT Joseph Raymond `lasse, Paris, France, assignor to Hotchkiss-Brandt, Paris, France, a corporation of France Filled .lnly 10, 1961, Ser. No. 122,988 Claims priority, appiication France .luly 11, 196i) 7 Claims. (Cl. 1412-50) The present invention relates to openable n arrangements for self-propelled projectiles yshot from a launching tube, which implies that the fins of the Ifin-arrangement must be folded toward the axis of the projectile to permit the latter to travel through the tube, the fins opening out or unfolding as soon as the projectile leaves the tube.

The invention more particularly relates to a iin arrangement of the type in which the ns open out by pivoting in longitudinal radial planes about pivot 4axes which are orthogonal to the longitudinal axis of the fin arrangement and located toward the forward ends of the fins, the forward direction corresponding to the direction of motion of the projectile on its trajectory.

The object of the invention is to provide an arrangement of this type which is so improved as to be simple in construction and faultless in operation. The iin arrangement according to the invention comprises fins combined with a thrust device which is concentric with and movable along the longitudinal axis of the iin arrangement between a forward position in which the ns are folded back and a rear position in which the fins `are opened out and maintained in this opened out or unfolded position by the thrust device, the latter being combined with means for exerting thereon an axial thrust which tends to shift the thrust device from the forward position to the rear position.

In one embodiment of the invention, the thrust device comprises a series of pistons or push-rods movable in cylindrical apertures formed in a iin support, the axes of the apertures being parallel with the longitudinal laxis of the fin arrangement, the thrust device further comprising a ring concentric with the axis of the iin arrangement and interposed between the push-rods and fins. However, it must be understood that the scope of the invention is not limited to this preferred embodiment.

Further features and advantages of the invention will be apparent from the ensuing description, with reference to the accompanying drawings to which the invention is in no way limited.

ln the drawings:

FIG. 1 is a longitudinal sectional view of a lin arrangement according to the invention, the fins being in the folded back position.

FIG. 2 is a corresponding rear end view;

FIG. 3 is a longitudinal sectional View of the n arrangement, the tins being in the opened out position;

FIG. 4 is a sectional view taken Ialong line 4 4 of FIG. 3',

FIG. 5 is a half longitudinal sectional view of a iirst alternative embodiment of the invention, the lins being in the folded back position;

FIG. 6 is a half rear end view of the embodiment shown in FIG. 5;

FIG. 7 is a half longitudinal sectional view of the embodiment shown in FIG. 5, with the ns in the opened out position;

FIG. 8 is a half sectional view taken along a line 8 8 of FIG. 7;

FiGS. 9 and 10 are longitudinal sectional views of a second alternative embodiment of the invention, the ns being shown folded back and opened out respectively;

FIG. 11 is a half longitudinal sectional View of a third 3,098,446 Patented July 23, 1963 alternative embodiment of the invention with the ns folded 'back in the state of rest;

FIG. l2 is a corresponding half rear end view;

FIG. 13 is a half longitudinal sectional view of the third alternative embodiment with the tins opened out, and

FIG. 14 is a lhalf sectional view taken along a line 14-14 of FIG. 13.

In the ensuing description, the forward `direction corresponds to that in which the projectile travels on its trajectory; in FIGS. 1, 3, 5, 7, 9, 10, ll and 13 the forward end is situated on the left.

In the embodiment shown in FIGS. 1 to 4, the device according to the invention, which constitutes both the propelling jet nozzle and the iin arrangement, is adapted to be fixed in the rear of the body C of a self-propelled projectile, and in particular a rocket, which is shot from a launching tube.

This device comprises a metal support 1 provided at the forward end with an external screw thread 2 for screwing into the tapped rear end of the body C. The support y1 has an axial stepped aperture having an axis X-X corresponding to the axis of the body C. This aperture comprises a large counterbore 3, a smooth portion 4 of smaller diameter, a tapped portion 5 of slightly smaller diameter forming with the portion 4 a shoulder 6, and a smooth rear portion 7.

Engaged in the portion 4 is a ring 8 constituting the convergent portion and neck of a single axial nozzle, generally designated by the reference character T, provided for the ejection of the propelling gases emanating from the usual propelling charge (not shown in the drawing) disposed within the body C of the projectile. The nozzle T is completed by a rear nozzle body 9 having an axial aperture throughout in a lform of a rearwardly divergent passageway 10. The body 9 is screwed in the tapped portion 5 of the axial aperture of the support 1 and is provided at its rear end with the usual small inner fins 11 which impart a rota-ry motion to the projectile about the longitudinal axis X-X thereof.

The body 1 of the lin yarrangement comprises at the forward end in the -counterbore 2, a ring 12 of a heat insulating material adapted to protect this support from the heat and support the `self-propelling powder block (not shown in the drawing). Disposed between the ring 12 and the support 6 is a metal washer 13 and a washer 14 composed of a heat insulating material.

Provided in the rear face 16 of the support 1 is a forwardly convergent aperture 17 having an axis X-X exelnded by a cylindrical aperture 18 visible in particular in Formed in the rear portion of the support 1 Iare radi-al and longitudinal recesses 19 which make therebetween equal angles x (FIG. 4). -A fin 21 of the iin arrangement is disposed in each of the recesses 19; each fin is pivotab-le in its longitudinal middle plane of symmetry, such as Y-X (FIG. 4), labout a transverse axis, such as Z-Z, which is orthogonal to the longitudinal axis X-X of the projectile and iin arrangement. A pin 22 having `an axis Z-Z is engaged in a blind hole formed in the support 1 (FIG. 4).

The fins 21 are pivotable about their respective axes Z-Z between the folde-d back position shown .in FIGS. l and 2 and the unfolded or opened out position shown in FIGS. 3 and 4.

Before launching the projectile, the fins are maintained i-n the folded position shown in FIGS. 1 .and 2 and have lsuch shape that in this folded position the inner edge 3 the body C of the projectile. The fins are held in this folded position by an outer ring 27 (FIG. 1) adapted to be removed when the projectile is placed in the launching tube.

The assembly just described is completed by a thrust device which, when the fins have been released from the ring 27 and issue from the launching tube, opens them from the position shown in FIGS. 1 and 2 to the position shown in FIGS. 3 and 4.

This thrust device comprises in combination, on the one hand, a single ring 29 slidable in an annular space between the cylindrical face 24 of the body 9 and the cylindrical aperture 18 of the support 1, and, on the other hand, a series of cylindrical push-rods 30 constituted by pistons movable in cylindrical apertures 31 in the support 1 which are disposed on a circle concentric lwith the nozzle T and `are parallel with the axis X-X, each of the cylindrical apertures 31 communicating with the :forward face of the support 1 in alignment with an aperture 32 which is formed in the washer 13 and thus puts the corresponding aperture in permanent communication with the interior of the body C of the projectile.

Each push-rod 30 is provided with a sealing ring 33 and the cylindrical apertures 31 are so disposed that each push-rod or piston 30 bears at its rear end against the ring 29.

The latter comprises a at rear face 34, a cylindrical outer lface 35 and an outer flange 36 at its forward end. These various faces of the ring 29 are adapted to cooperated with a forward cam portion of each fin 21. This .forward portion has, when viewed from the side (FIGS. 1 and 3), a substantially ogival shape in that it is defined by an outer convex edge 37 and a flat inner edge 38 in which a notch 39 forms a pointed portion 40.

The device according to the invention operates in the following manner:

When being stored, the projectile has its tins folded back in the position shown in FIGS. 1 and 2, their being held in this position by the ring 27. The ring 29 of the thrust -device is then in its extreme forward position against the end of the bore 18 in the support 1 and the push-rods 30 are in their extreme forward position in the immediate vicinity of the apertures 32 in the ring 13.

When the projectile is to be placed in the launching tube, the rear ring 27 is previously removed. As soon as the Aself-propelling charge has been ignited, the gases produced by this charge are ejected through the passage- Way of the nozzle T and the jet propels the projectile While a small part of these gases enter, upon ignition of the charge, the cylindrical apertures 31 by way of the oriiices 32 and rearwardly urge the push-rods 30 which cause the ring 29 to move rearwardly. As the later is, when at rest (FIG. 1). in contact by its rear face 34 with the portion of the notch 39 'forming the pointed portion 4() of each iin, all the tins, which are free as soon as the projectile lissues from the launching tube, are swung about their pivot axes in the direction of arrow f1 (FIG. 1).

Thus, the fins open almost instantaneously.

It will be understood that in varying the number, and to a certain extent the diameter, of the push-rods 30 the speed of opening of the tins can be varied. This is of great interest under certain launching conditions (rocket launching with the forward part in the shape of an ogive) The position shown in FIGS. 3 and 4 represents the end of the opening out of the tins, since in this position the ring 29 reaches under the action of the push-rods 30 the extreme rearward position in which the flange 36 of the ring abuts against the convex portions 37 of the forward parts of the fins, whereas the iiat portion 38 and the pointed portion 40 of each tin abuts against the cylindrical outer face 35 of the ring. In this opened 4 position of the iins, there is thus obtained an automatic reciprocal locking of the ring`29 and tins 21.

The tin arrangement, which is perfectly locked in the open position, stabilizes the projective on its trajectory not only during the acceleration period due to the continued ejection through the nozzle T of the gases produced from the combustion of the `self-propelling charge, but also during the deceleration period after combustion of the propelling charge, in other words, from the instant of launching until impact on the target.

As will be understood, the device is proof against any mishap and in particular any wedging of the folded fins, the latter being opened without use of the usual iin opening spring or springs which are always fragile elements.

FIGS. 5 to 8 show a lirst alternative embodiment of the invention-in which the nozzle T1 is in one piece and screwed at 41 in a n suppotr 1a -consisting of three elements 42, `43 and 44. The element 42 is provided with an external screw thread `for screw-threadedly engaging the device constituting the nozzle and iin arrangement in the rear tapped end of the body C of the projectile.

The element 43 is screwed-threadedly engaged at 45 on the element 42 and comprises recesses 19EL each of which is adapted to receive one of the lins 21a. In .its outer face, the element 43 has a peripheral shoulder 46 which faces forwardly and constitutes the rear portion of a groove adapted to receive a ring 47, the other portion of the groove being formed by the rear -face 48 of the third element 44. rIlhe latter is provided with recesses 19b each of which is in alignment with a recess 19a of the element 43 to permit the free movement of the fins 21a about the ring 47 which constitutes a pivot pin for each lin.

The iin 21a co-operates with a thrust device comprising, as in the rst embodiment, a single ring 29a combined with push-rods or pistons 30 movable in cylindrical apertures 31 which are provided in the element 42 and communicate with the interior of the nozzle body by way of a radial recess 49.

In this embodiment, the edge of the forward end of each n 21' consists of two straight portions 50 and 51 forming a cam and the ring 29a comprises two conical chamfers, namely a rear chamfer 52 and a forward chamfer 53, the latter being provided on the rear face of an outer liange.

At rest (FIG. 5), the ring 29a bears by its chamfer 52 against the straight portion 50 of each tin 21a in the folded position, and when the ring 29EL is shifted rearwardly by the push-rods 30 the chamfer 52 causes the ns to swing open until the position shown in F-IG. 7 is reached, in which there occurs a locking of the ring 29a and the fins 23.5L by the bearing of the portion 50 of the edge of each fin against the cylindrical outer face of the ring 29a, on the one hand, and by the contact between the chamfer 53 of the ring and the portion 51 of the edge of the iin on the other hand.

FIGS. 9 and 10 show a second alternative embodiment of the invention which constitutes merely an openable fin arrangement. This embodiment has no self-propelling gas jet nozzle and is consequently of utility on a projectile adapted to be launched or shot solely by means of a launching charge outside the projectile in the manner of a shell, or to be cast off from an aircraft. The iin support 1b comprises the screw thread 2 for mounting in the body C of the projectile and the tins 2lb are mounted thereon for pivotal movement about transverse axes in recesses 19b in the support, the pivot axes being constituted by tubes 22h. The ns are opened out without use of a ring common to all the tins, as in the previous embodiments, but -directly by means of individual pushrods 30b movable in cylindrical blind cavities 31h. Each push-rod is biased rearwardly by a spring 54 located between the end of the cavity 31*D and the end of a hole 55 in the corresponding push-rod 30h. This hole 55 communicates with the rear end of the push-rod by way of an orifice 56 adapted in particular to balance the pressure prevailing in the gun tube and cavity 31".

As will be understood, in the embodiment shown in FIGS. 9 and 10 the fins are opened solely by the action of the springs 54 which are compressed when the fins are folded back and extend when these fins are free to move so as to bring the latter to the position shown in FIG. in which the push-rods 30h and the ns 2lb become mutually locked.

-It should be understood that, if desired, the action of the springs 54 could be replaced by the pressure of the gases produced upon tiring by a certain amount of powder placed in the cavities 31b in place of, or in addition to, springs 54. Upon firing, ignition of this powder could be achieved by way of the orifices 56 in the rear ends of the push-rods 30b and, if desired, by way of passage-ways 58 (FIG. l0) formed in the support 1b.

By suitably choosing the amount of powder, the size of the grains and the sizes of the orifices 56, and passageways 58, it could be arranged that a certain pressure prevails during a certain period of time in the cavities 31b at the moment when the projectile issues from the gun tu-be. This pressure could replace or, if desired, complete the action of the fin-opening springs 54.

In the alternative embodiment shown in the FIGS. 11 to 14, the device adapted to be fixed in the rear of the body C of the self-propelled projectile comprises a support 1c screwed at 2 in this body. Fixed to this support is the axial nozzle T2 having the convergent portion 8 and the divergent portion 9. Disposed forward of this nozzle and the support 1 are protecting washers 13 and 14.

Provided in the rear peripheral portion of the support 1C are radially and longitudinally extending recesses 19c in each of which is engaged a iin 21c of the fin arrangement. Each fin is pivotable about a transverse pivot pin 22 which is a force t in the iin and disposed in an annular toroidal groove 60 formed in a rear recess 61 in the support.

To facilitate the introduction of the pins 22, ytheir ends 62 (FIG. 14) are tapered to snit the diameter of the groove 6i) so as to fit against its curved annular surface.

The tins are mounted in the recesses 19c by introducing their pins 22 into the recess 61 until they engage in the groove 60, before the nozzle T2 has been screwed in position. Once the latter has been mounted together With the fin opening ring, the pins 22C can no longer leave the groove 60.

The assembly is completed by push-rods 30 slidable in cylindrical apertures. Each push-rod is adapted to open a fin from the position shown in FIG. 1l to that shown in FIG. l3 under the effect of the thrust of part of the gases from the self-propelling charge, these gases passing through an annular slot 49 into the apertures for the push-rods.

Although specific embodiments of the invention have been described, many modifications and changes may be made therein without departing from the scope of the invention as delined in the appended claims.

Having now described my invention what \I claim as new and desire to secure by Letters Patent is:

l. The combination of an ejection nozzle for the expulsion of propelling gases and an openable iin arrangement for use on a self propelled projectile, the combination comprising a body adapted `for being connected to the projectile, the body having `a longitudinal axis and being provided with an axially extending opening passing through the body, the body being further provided with a plurality of cylindrical apertures angularly arranged around said opening at a common distance therefrom and extending parallel to the axis of the body, a fixedly supported nozzle in the opening for expelling rearwardly gases from the projectile to cause a thrust to be exerted thereon, a plurality of tins supported on said body for pivotal movement about transverse axes to enable opening and closing of said fins in longitudial radial planes, a piston slidably supported in each of said apertures and adapted for movement rearwardly in the associated aperture under the propelling action of the gases from the projectile, means defining a cylindrical bearing element rigid with and coaxial with the body and an intermediate ring of annular shape positioned between the fins and the pistons, the ring being guidedly mounted on the bearing element for sliding movement along the bearing element in a longitudinal direction, the ring being operatively associated with respect to the pistons and fins such that the ring undergoes sliding movement in a longitudinal rearwardly direction under the action of the pistons, when the latter are displaced by the propelling gases, to exert a .force on the iins to cause the latter to open, whereby the ring distributes the overall force exerted thereon by the pistons uniformly to the fins so that the latter open uniformly and symmetrically from the body.

2. The combination as claimed in claim 1 wherein there are provided as many of said apertures as there are ns whereby there is a piston for each iin.

3. The combination as claimed in claim 1 wherein said body has a rear end in which is provided an annular axial recess in part surrounding the axially extending opening, the body being provided with an annular toroidal groove coaxial with the body and accessible through said recess, said body having radial slots formed therein extending Iforwardly from said rear end in an axial direction beyond said recess -for accommodating said fins, each fin having an aperture adapted for alignment with the toroidal -groove and a pivot pin for each fin in interfering fit in the aperture of the associated iin, said pins having opposite ends extending from the fins supported in the toroidal groove to pivotally support the respective fins from the body.

4. The combination as claimed in claim 3 wherein said opposite ends of the pins are of frusto conical shape for accommodation in the toroidal annular groove.

5. lIn a foldable iin arrangement for a self-propelled projectile the combination comprising, means defining a body :having a support portion adapted for being connected to the projectile and an ejection nozzle portion rigid with the support portion, the body having a longitudinal axis, a throughway axial opening formed in the body and extending through the support and nozzle portions lfor the passage of the projectile propelling gases from the projectile, a plurality of apertures arranged on a circle concentric with said axis and formed in the support portion, the apertures extending in a direction parallel with said axis and communicating with the opening, pistons respectively mounted in the apertures Afor sliding movement in a direction parallel with said axis, a plurality of iins supported on the support portion for pivotal movement about transverse pivot axes in longitudinal radial planes relative to said body between a folded position and an unfolded position, a ycylindrical outer bearing face provided on and coaxial with the body and extending longitudinally along a part of the nozzle portion, an annular ring encompassing and slidably mounted on the bearing yface for sliding movement axially of the body, the ring being distinct from and located between the pistons and the fins, the pistons being capable of abutting and urging the ring axially rearwardly and each fin having a portion capable of being engaged by the ring and urged by the ring to pivot rearwardly about said pivot axis, and abutment means for limiting the rearward displacement of the ring when the iins have reached their unfolded position, whereby when the pistons are rearwardly urged by the propelling gases passing through the axial opening the force exerted by the pistons is uniformly transmitted by the ring to said portions of the fins and the latter are unfolde'd in a symmetrical manner.

6. The combination as claimed in claim 5, wherein the portions of the fins have faces adapted to be engaged by the ring in a substantially cylindrical plane of contact co- Y axial with the body when the ins are in their unfolded position, and said pivot axes are contained in a plane which is perpendicular to said longitudinal axis and intersects said plane of contact, whereby the fins are blocked in their unfolded position and prevented from pivoting in either `direction about the pivot axes by the ring which is interposed between the faces of the portions and said outer bearing face.

7. The combination as claimed in claim 5, wherein the pistons abut the ring and the ring engages the portions of the fins substantially in a common cylindrical plane having an axis coincident with said longitudinal axis.

References Cited in the le of this patent UNITED STATES PATENTS Moore Dec. 19, 1944 Gould Aug. 6, 1957 

1. THE COMBINATION OF AN EJECTION NOZZLE FOR THE EXPULSION OF PROPELLING GASES AND AN OPENING FIN ARRANGEMENT FOR USE ON A SELF PROPELLED PROJECTILE, THE COMBINATION COMPRISING A BODY ADAPTED FOR BEING CONNECTED TO THE PROJECTILE, THE BODY HAVING A LONGITUDINAL AXIS AND BEING PROVIDED WITH AN AXIALLY EXTENDING OPENING PASSING THROUGH THE BODY, THE BODY BEING FURTHER PROVIDED WITH A PLURALITY OF CYLINDRICAL APERTURES ANGULARLY ARRANGED AROUND SAID OPENING AT A COMMON DISTANCE THEREFROM AND EXTENDING PARALLEL TO THE AXIS OF THE BODY, A FIXEDLY SUPPORTED NOZZLE IN THE OPENING FOR EXPELLING REARWARDLY GASES FROM THE PROJECTILE TO CAUSE A THRUST TO BE EXERTED THEREON, A PLURALITY OF FINS SUPPORTED ON SAID BODY FOR PIVOTAL MOVEMENT ABOUT TRANSVERSE AXES TO ENABLE OPENING AND CLOSING OF SAID FINS IN LONGITUDINAL RADIAL PLANES, A PISTON SLIDABLY SUPPORTED IN EACH OF SAID APERTURES AND ADAPTED FOR MOVEMENT REARWARDLY IN THE ASSOCIATED APERTURE UNDER THE PROPELLING ACTION OF THE GASES FROM THE 